Hazard Monitoring (Ground check)

Configures parameters for scanning hazards on ENC (charted hazards), highlighting them on the chart, and generating cautions within a strip whose width includes the set distance to hazards, the current positioning error (maneuvering lane), as well as in the bow and stern sectors.

The hazard detection distance is set by the navigator or calculated automatically based on the vessel’s speed and the set hazard detection time.

When navigational hazards are detected within the lane occupied by the vessel, accounting for drift, position determination error, and CATZOC, an audible alarm is generated. In general, the distance to hazards set by the navigator should be greater than the automatically calculated maneuvering lane.

Navigational hazards detected in the bow sectors are displayed on the off-scale dangerous bearings indicator.

Navigational hazards detected in the stern sector are highlighted on the chart to monitor the safety of the vessel’s turn in a narrow channel or when proceeding with significant drift.

Monitoring Settings (Ground check settings)

Important

Designed for configuring parameters of navigational hazard highlighting on ENC, monitoring sector width, and navigational hazard monitoring lane.

Monitoring of navigational hazards, the safety contour in the vessel’s lane, and their display on the off-scale hazard indicator are performed regardless of the ENC display highlighting state.

Before using ECDIS, configure the hazard monitoring parameters in the sections: Ground check and Alarm filter.

Accessing settings

Menu path
→ → Grounding check → Settings

Monitoring configuration parameters

No.	Parameter	Description
1	Safety contour	Selected from among the depth contours of the largest-scale ENC cell at the vessel’s position with the nearest value greater than the safety depth
2	Safety depth	Calculated based on the current vessel draft and current water level
3	Safety height	Calculated based on the current vessel draft and current water level
4	Draw Safety Zone	Enables display of the calculated navigational safety zone
5	Draw Sector	Enables display of the hazard monitoring sector
6	Set objects filter	Opens the Alarm filter window
7	Detection time (Forecast)	Performed either by time (dynamic forecast) or Detection range by a set distance (static forecast). Depending on the navigator’s preference, enter the value in the numeric field: time in minutes, or distance in km/nautical miles. Based on the set parameters, the radius of the hazard scanning sector ahead of the vessel will be formed.
8	Sector angle	Sets the width of the hazard scanning sector. The sector is calculated relative to the vessel’s course vector. The full sector angle is entered.
9	Draw Alert Limits	Enables display of the alert generation boundaries for detected navigational hazards — the dynamic maneuvering lane
10	Alert priority	Select the alert category for detected navigational hazards: Warning or Caution
11	Account the ENC Accuracy	Enables automatic accounting of CATZOC from the largest-scale ENC under the vessel’s position. ECDIS accounts for CATZOC values of categories A1 and A2. If the CATZOC value exceeds A2 (RMS > 20 m), ECDIS uses the manually entered CATZOC value in calculations
12	—	Current CATZOC value, CATZOC category, and the corresponding positional accuracy of underwater topographic features
13	Manual input	Manual entry of the CATZOC value. The value for CATZOC > A2 (RMS > 20 m) to be accounted for in calculating the maneuvering lane and navigational safety zone

Tip

When navigating in areas with abundant navigational hazards at low speeds, it is recommended to set the forecast method by time for the monitoring sector and dynamic lane.

In this situation, selecting the forecast method by distance may result in excessive clutter on the ENC with highlighted hazards and loss of situational awareness.

When selecting the Detection Time method at high speed, the scanning area will increase and the load on ECDIS will be significantly higher, which may cause user interface response delays, especially when navigating in areas with abundant navigational hazards. This is due to the large volume of objects being processed on the ENC. The most optimal monitoring method depends on the vessel’s characteristics and the navigation area.

Maneuvering lane calculation

The maneuvering lane is calculated using the formula:

\(B_{t} = L\sin(drift) + B\cos(drift) + t_{c}\sin(drift)V\)

where:

• \(L\) – length of the vessel or tug-barge combination, in meters

• \(B\) – beam of the vessel or tug-barge combination, in meters

• \(drift\) – current drift angle of the vessel

• \(V\) – current vessel speed, in m/s

• \(t_c\) – lead time equal to 180 seconds, in sec.

Navigational safety zone calculation

\(AL = B_{t}\sqrt{m^{2} + c^{2}}\)

where:

• \(B_t\) – vessel maneuvering lane width

• \(m\) – current root-mean-square error of the vessel’s position, entered manually by the user or received from the $--GSA sentence

• \(c\) – current CATZOC

Alarm Filter configuration

Configure the highlighting of navigational hazards on the chart in the Alarm Filter.

Menu path
→ → Grounding check → Alarm Filter

No.	Parameter	Description
1	Navigational hazards	Enables/disables monitoring of point objects with a navigational hazard attribute
2	Areas with special conditions	Enables/disables monitoring of objects in the group
3	Areas with special conditions group	Detail of objects in areas with special navigation conditions
4	Safety contour	Enables/disables monitoring of the safety contour
5	User defined areas with special conditions	Enables/disables monitoring of objects belonging to the group
6	User defined areas with special conditions group: - Information areas (Anchor Berth, Cargo transhipment area, Fishing ground) - Protected areas (Dumping Ground, Incineration area, Pipeline area, Precautionary area, Cable area, Fairway, Territorial sea area) - Ships routing system and ferry routes - Miscellaneous (Depth contour, Continental shelf area, Exclusive zone)	Detail of objects in user-defined areas with special conditions

Configuration recommendations

Before configuring monitoring:

1. Ensure the current vessel draft is set correctly

2. Verify the sensor settings are correct

3. Set the current water level for correct selection of safety contour and safety depth

Safety configuration:

1. Select the forecast method (time or distance)

2. Set the monitoring sector and lane parameters

3. Configure the object filter for monitoring

4. Enable sector display on the chart for visual monitoring

Warning

The use of hazard monitoring does not replace the navigator’s professional judgment. The system warns of potential hazards, but the officer of the watch always makes the final safety decision.

Hazard Indication

Chart indication

Depending on the configured monitoring parameters, a scanning area is formed around the vessel symbol: stern and bow sections.

Objects within this area that belong to monitoring groups will be highlighted on the chart.

Additionally, the scanned area contains a dynamic sector-lane. For objects within the dynamic scanning lane, Alarms will be generated. Alarms are generated regardless of the display highlighting settings. |

Scanning area elements

No.	Element	Description
1	Own ship on the chart	Current vessel position
2	Speed vector of the vessel with forecast for the set time	The vector shows the direction and speed of movement (in the example: 5-minute forecast)
3	Bow section of the scanning area	Constructed based on the Sector-lane width. Alarms are not generated for objects in this area; only highlighting is performed (if enabled)
4	Stern section of the scanning area	The center of the sector is located at the CCRP and the sector equals 180 degrees. The radius of this sector is equal to half the Sector-lane width. Alarms are not generated for objects in this area; only highlighting is performed (if enabled)
5	Dynamic hazard scanning Sector	The hazard scanning area ahead of the vessel
6	Dynamic hazard scanning Lane	Alarms are generated for objects within the scanning lane
7	Point object highlighting	Point hazards within the scanning area
8	Area object highlighting	Area hazards within the scanning area

Charted hazards

Navigational hazards are always displayed on the **Hazard indicator**. List of charted hazards that generate alarms:

Navigational hazards

1. Coastline

2. Safety contour

3. Isolated underwater dangers

4. Buoys and beacons

5. Obstructions

6. Bridges, if the vertical clearance is less than or equal to the value set in the settings

Important

Alarms are generated only for objects within the dynamic scanning lane.

Hazard highlighting is performed regardless of the Alarm filter settings and safety sector display enabling.

Important

Highlighting of point and area navigational hazards is performed based on the largest-scale ENC located under the vessel’s position.

Monitoring specifics

Bow scanning sector:

• Provides advance hazard detection

• Performs preliminary object highlighting

• Does not generate alarms, only visual warning

Stern scanning sector:

• Monitors the safety of the vessel’s turn

• Especially important when navigating with significant drift

• Useful when proceeding in a narrow channel

Dynamic lane:

• Formed based on the configured safety parameters

• Accounts for the vessel’s current speed and heading

• Generates audible and visual alarms

Warning

Hazard monitoring system alarms must not be ignored. Upon receiving an alarm, immediately assess the situation and take measures to ensure the vessel’s navigational safety.

Monitoring recommendations

Preparation for the voyage:

1. Configure monitoring parameters in accordance with the vessel’s characteristics

2. Set the current vessel draft

3. Select the object filter for monitoring

4. Enable the safety sector display on the chart

During navigation:

1. Monitor highlighted hazards on the ENC

2. Pay attention to the off-scale hazard indicator

3. Respond immediately to audible alarms

4. Analyze the position of hazards relative to the vessel’s course

Safety monitoring:

1. Regularly verify that monitoring settings are up to date

2. Regularly update the current vessel draft in ECDIS settings

3. When navigating in areas with tidal effects, regularly update the water level value and the time of its application

4. When speed or navigation conditions change, revise the parameters as necessary

5. Do not rely solely on automatic monitoring — maintain visual lookout

Tip

Using static forecasting (forecast by distance) provides more stable system operation and lower ECDIS processor load, especially in areas with a limited number of navigational hazards.